Electrical switching device



G. N. HUGHES ELECTRIQAL SWITCHIG DEVICE Feb. 17, 1931.

Filed May 18, 1928 2 Sheets-Sheet l Dwa Y M ATTORNEY Feb. 17, 1931.

G N. HUGHES 1,793,402 ELECTRICAL SWITCHING DEVICE Filed May la. 1928 2sheets-sneer 2 ZM @in JJ J6 ATTORNEY key with 'winch Patented Feb. 17,1931 V GY iv. Beginns, 'or .rLTL incitera ricominciajswncmae twiceurpmi-cation inea 'may is,

This invention app ertains'to improvements inl electricalswitchingdevices-generally, and more particularly to a multipole blocktype of such devices for use intesting eflectrical l measuringinstruments, and otherjelectrical apparatus ofvariosclas'ses anddescriptions.

An object of the invention :is to provide a Y switching device of thekclass set ort h,`-L which Y is o'fan extremely sim-pli-ed lont-durableand Y efficient construction and arrangement of expensive tomanufacture.

Another object of thejinvention is -to vpro- -vid'e an electrical testbloc-k, as hereinloefore parts, and Which will bei comparatively yin- Y16. characterized, which will require only-a minimum amount of. space"kon a switch looardl or panel, and which will Vbemore `easily andVquicklyy installed in position and wiredfin a 'desired circuit'tvithless dangerof open or 2 0' short circuit than has heretofer e been the case in the installation of` known types of such devices. y y A A furtherobjeotgofthe invention is to `provide a test switch block `of the naturehereinbefore mentioned, wherein the Amovable switch-members thereof willbe key operated, so that the manipulation of the same may only belaccomplished ley-an authorized person or ersons.:V With theforesoingend ethefeeuallyimportantobjects `and advantages 1in view/,-the invention resides inthe kcertain new and useulcombination,,construction and arrange.-l

ment of Lpar-ts and circuits as will loe hereinafter more fully'describedfset forth in t-he appended claims, .and illust-rated inthea'ccoinp anying; drawings, :inrwhich Figgaire 1 isa top fplan "View ofla@practical minemment of then'ventonwth the cover pcrtionthrcfremved, j

erigere s is a vertical 11o' `"rudtnalfsctien tafken on theliiief'T-Zt1,

` Figure isM avrti'icalitr talrenonthel 63;3 4fFiitifrel Fijlireil 1s' jersp'l' .e lo

the individual switch lnni-V he'rslare tolj'operated.

Figure 5 is a diagrannnatic viei'voifianarrangement oi "ci'ciit"connections to :the Tim'- cover .in place". Any suitable, sealing means)proved .testfblock for testingprotectiverelays "Ffgure 6 is aj view y similarto 'that of kFigure Q5, but shavingen; @Heil-sment if Cil'- cuitconfnection s employed ,'i'or t'estingvariouselectr-ical.measuring"instruments.

Reffefmfrt@ f the 1 drew-mss, wherein like chalracter'sof.reference-designat-e correspondagree'ementnewer'views.eeeof?, theembodimentof the,invention',asrshoivn fcc "thereinbvway o-eiiample,comprises a base .iblroolr 10,. vvh ili.is preferally of rectangular lal suitable 4insulating material, and-1s fprovldedvvith posts or the.lilrefll rising from each o 'fits'corners to sup'- 65 port thereon acover 12. The cover 12, 'which mayiloe of metal, or any other suitableor desired material, has j s'ide andiend'flang'esdepending. from itstop; Wallfivlrich snugly e'ngafgejabout the oppositesicleandend edges170 suitable openings to engage over 'the upper threaded endsof theposts 11. Thesefthreaded en dsfof fthe posts 11 are preferably of areduced diameter t'o provide shoulders `at,' their lotve-r connectedends on which the cover 12 rests vhen placed in position yon the lease10., vand 'nuts A13 are engaged fon the '.tlirea'dedwends of posts 1 1to secureA the Knot einem@ eempldyzd. in comme@ with the coversecur'ngnuts 13 to Kp re'v e'ntft'lie unanthori'zed removal 4t'h'esaneivhen Ithey are Helly iplf' ,ingestion on the reen, aswheathetstbibekgn its entirety, has been instaleditsoperative-posift'ion.

@semifinfalle] downwardly through the base to have their lower endselectrically connected to circuit leads tobehereinafter designated. The

seveial stationary contacts of each parallel set of the same arepreferably of rectangular metal block formation and` arranged intransverse alinement with their-,opposed end edges bi'furcated, as at24; Toretain the contacts of each transverse pair thereof in positionwith their bifurcated ends inthe desired opposed relation, pins or studsvare engaged in the base 10, and the contacts,at ,o-Iieside of therespective contact studs or screws 14", 1 16, 17, 18', 19, 20.', .22.and123 for the purpose.

Disposed on the and midway between each pair Vof the complementalstationary contacts 14, 19,15, 20; 16, 21; 17, 22; and 18, 23 arebridging contacts or switch blades 26,27, 28, 29 and 30,

respectively, which are each preferably mounted vfor quarter turnmovements only on the upperY end portions of pivot members yor screws 31beneath the heads thereof,sub stantially as shown, suitable supportingmembersor washers 32 being positioned on the bolts or screws 31'beneath`the bridging contacts or switch blades 26, 27, 28, 29 and`30 to alinethe same with the bifurcations in the stationary contacts with whichthey cooperate.

Formed in the upper face of each ofthe bridging contacts or switchblades`26, 27, 28,

'29 and 30 are a pair of slots or recesses 33,

which are preferably arranged in alinement at oppositepoints'diametrically of the headed portions of the pivot members orscrews 31 associated therewith. Th-ese slotsy or re-' ycesses 33 are tobe engaged by the complemental projections 34 formed lat' the lower endof a key 35, by means of which the bridging contacts or switch blades26, 27, 28, 29

and are tol be actuated' to circuit closing or on and circiutopening oronf positions of operation withres'pect to the complemental' pairs ofthe stationary contacts aforesaid.

Y Between the projections 34, the body of the the upper headed portionsthereof. These "bridging contacts ,or switch bladesV 37 and 38 are eachalso providedwith'slots or'recesses l33 inthe upper faces of the samefortli'e enlrey is recessed, as at 36, to a depth sufiicient' to admitof theV straddling ofthe headed portions of the pivots 'or screws31..,by the same, and to allow for the proper engagement oftlieprojections 34 with the slots or recesses 33. l

' Also'disposedon the upper side of the base 10, preferably-between thestationary contacts 15 and 16, on the one hand, and the contacts 16 and17 onthe othery hand, area pair *of identical bridging contacts orswitch blades37 and38', Awhichvare mounted for v`limited turning.linovemens on .pivotsV Aor screws 39 and40 respectively, and beneathupper side of the .base 10V 38 therewith, the stationary contacts 16a1idl 17 yare also'bifurcatedat their 'outer ends, and after thesame manneras the formation of thebifurc'ations 24 at tlieinn'er ends of all kofthe several contacts 14, 15, 16,17, 18,

19, 20 21, 22and 23, inclusive. Asv bestV shown "in Figure 1, theopposite'ends of the bridgingl contacts or switchblades 37 and 38 areangularly offset in opposite directions,

wherebythe inner ends of the same will en-v gage the bifurcations atthe` inner ends of the f stationary contacts 15 and 16, and the oppositeorouter ends thereof with the bifurcations `at the 'outer ends of thestationary contacts 16 and r17, the purpose of which arra-ngement willbehereinafter morefully explained.' To allowfor thedesired engagement ofthe opposite ends of the bridging contacts or switch` blades 37 'and 38in the bifurcations of the stationary contacts 15, 16 and 17 as Vbeforeindicated, suitable supporting membersV or washers 39asimilar tothesupporting members orvwashers 32 iwill be engaged on'the i i pivotsjorscrews 39 and 40. l In-Figure 5,-the improved test block, as

ythus constructed and arranged, is shown con-- nect'ed in a circuit fortesting protective relays or the like,` the circuit connections where-Aof'beingas follows: from the three terminals ofa current'y transformerT, coupled to the main line'conductors a, b and c, tap offs'40,

41y and 42are connected directly to the binding studs or screws 1 5, 16and 17,fof thc stationary contacts 15, 16 and 17 while two conductors 43and 44 from a control sourcc (not shown) lead' to.l and connect thebinding studs or screwsv 14 and 18 of the stationary :contacts 14 and18,"a trip coil 43afbeing, as

usual, connected ginon. the conductor 43.

The several stationary contacts 19, 20,21, 22

and 23 are, iii-turn, connected respectively by thejciicuit leads 45,46, 47, 48 and 49 of av pair of protective relays 50. All ofthe-foregoing rvcircuit 'connections are to 'bc'hercinafter designated'asthe permanent circuit'- connections of this particular testing sys-ltem, as distinguished from the following teniporai'y test circuitconnections: a pair of coLnductors 51 and^52 are lead from thestationary contacts 19 and 23v toan opei'ation indicator (not shown),and a second pair of con-" ductors 5'3 and k54 from the stationarycontacts 21 andl22, the conductor 53 leading 55, ywhichvhas its otherterminal Yconnected to the other side of the latter circuit by aconductor 56.

. In the operation'ofntlie test block this hook up of'circuits, and withthe temporary' circuit conductors orleads 51, 52, 53 and 54 7disconiiecfed from the stationary contacts 19,-V

23, 21 and 22 respectively, the transformer short circuiting-bridgingcontacts or switch blade-s 37 and 38 in oli position, the line bridgingcontacts or switchV blades 26, 27,

' 28, 29 and 30 closed, and the main line circuit breaker (Z closed, therelays 50; will be operatively connected to line a, b, c throughtransformer T. `New to make a test on kthe relays 50, the temporaryconductors or leads 51, 52, 53 and 54 will be connected to the bindingstuds or screws 19'23, 21 and 22' of the stationary contacts 19,23, 21and 22, in the order named, when the bridging contacts or switch blades37 and 38 will be closed on the stationary contacts 15, 16 ,and 17,thereby short-circuitingthe transformer T, and thenthe bridgingcontactsv or switch blades 26, 27, 28, 29 and 30 opened. The relays-50will now be completely disconnected from the-Y otherwise permanent linecircuit connecbv the conductor 44' to the main lead c',

while the stationary contacts 15, 16 and 17 are connected by theconductors 40', 41 and 42' to the three terminals of the currenttransformer T', as in the first instance. The several stationarycontacts 19, 20,21, 22 and 23 are connected to the circuit leads 45',46',

47', 48 and 49' to the bank of electrical meas-A uring instruments to betested, after the same manner of the previous connection of the pro.-tective relays 50.

For the purposes of the present invention, the foregoing describedconnections also constitute the permanent connections for the testblock, while the temporary test connec-` nections are to be made as'follows A conductor 51' will be led from the stationary conl tact 15 toone terminal of a test meter 55', a second conductor 52 from thestationary coiitact 17 to a second terminal on the `meter 55', a thirdconductor 53 from the stationary contact 20 to a third terminal on themeter 55',

and a. fourth conductor 54' from the stationary contact 22 to a fourthterminal on the meter 55', while the three main terminals of stationarycontacts 15, 16 and 17,'but, after the temporary testfwiring is properlycon-V nected as liereinbefore indicated Jfor the same,

theY line bridging'contacts or switch blades 26, 27 28, 29'and 30 areopened, with the result that the current from the main line translformer'I" is shunted through the. test meter 55 asis required. v

blades 26, 27, 28, 29, 30, 37an`d. 38, the top To admit of theengagement of the key 35 v with thevseveral bridging contacts or switchwall 'of the cover 12 will be provided with a corresponding number ofvopenings Y therein forfthe purpose.

Vithout further description, it is thought.

that the featuresk and advantages of the inslilled in the art, and itwill of course-be understood that changes in the circuit connections,and in the type and value of the devicesem'pl'oyed may be resorted to,without departing from the spirit ofthe invention or its scope asclaimed.

vventionfwill be readily apparent to those Y Having thus fully describedthe invention, t

what is claimed is: f

1. In a deviceof the class described, a base of .an insulating material,a plurality-0f line switches spaced alongr said base and separate Yswitching elements mounted on said base and cooperative with thecontacts at one side or (l the adjacent of Vcertain of said lineswitches,

whereby to short circuit the same whenever desired or necessary.

2. In a device of the class described, aV base ofanjinsulating material,parallel 'rows of evenly spaced contacts mounted on said-base, a switchblade for each pair of oppositely disposed contacts, and separate switchblades cooperative with certain Vof the contacts in one of the rowsthereon onlyv to short circuit E,

theV same whenever desired or necessary.

3. v In a device of the class described, a base v of an insulatingmaterial, parallel rows of evenly spaced contacts mounted on said base,switch blades mounted on said base one between each pair oftheoppositely disposed contacts, said switch blades being arranged forlimited horizontal rotative movement relativeto the complemental of saidcontacts, and separate switch blades similarly mounted on said base andbetween certain of the said contacts at one side only of the tirst named,switch blades whereby to'short circuit the same whenever desired ornecessary.

GUYN. HUGHEs.

the meter 55' will be 'connected bythe conductors 57, 58 and 59 directlyto the mainline leads a', b' and c', respectively.

In the operation of the test block in this instance of its practicalapplication, it is not necessary that the transformerr T beshortcircuited through the closing of thebridging contacts or switchblades' 37 and 38onto the lll)

